European patent application 0 300 143 A2 discloses an automatic release ski binding having a housing accommodating a release spring and a sole holder. The sole holder is arranged on a bolt extending substantially perpendicular to the top side of a ski. This bolt has its lower end journaled in a support body arranged separately in the housing. The sole holder runs in a sliding fashion on the bolt and is acted upon by a compression spring urging it against the top side of the boot sole. It is in this manner that the sole holder is lifted within a certain tolerance limit if, for example, there is snow underneath the sole of the boot.
Similar sole holders are disclosed in the German patent publication 8,900,827 U and the French patent publication 2,662,612 A1.
European patent publication 0 228 524 A1 and European patent publication 0 271 694 B1 disclose other ski binding designs. In these designs the lateral jaws of the sole holder are not journaled on the previously mentioned bolts, which join the base plate and the upper part of the housing. In this respect, the lateral jaws are pivoted on pivot pins of an articulated quadrilateral, which consists of two levers arranged laterally in the housing, and a link connecting the two levers together.